Detachable coupling for lead pipes



(No Model.)

P. H. GUNDBRMANN.

DBTAGHABLE GOUPLING POR LEAD PIPES.

No. 597,497. Patented Jan. 18,1898* UNITED STATES PATENT EEicE..

PHILIP H. GUNDERMANN, OF CHICAGO, ILLINOIS.

DETACHABLE COUPLING FOR LEAD'PIPES.V

SPECIFICATION forming part of Letters Patent No. 597,497, dated January 18, 1898. Application Sled January 13, 1896. Serial No. 575,292. (No model.)

vlo al?, whom it may concern.-

Be it known that I, PHILIP I-I. GUNDERMANN, a citizen of the United States, :residing at Chicago, Cook county, Illinois, have invented certain newr and useful. Improvements in Detachable Couplings for Lead Pipes, of which I do declare the following to be a full, clear, and exact description, reference being had `to the accompanying drawings, forming a part of this specification.

The present invention has for its object to provide an improved construction of coupling whereby sections of lead pipe may be securely and tightly joined to iron orother hard-metal pipes, the invention being primarily designed to provide an improved detachable connection whereby the lead pipes of closets or basins may be conveniently and tightly joined to Waste or vent pipes.

Y It has been heretofore proposed to form a detachable lead-pipe coupling by forming the interiorsection of the coupling-that is to say, the section that enters theend of the lead pipe-with an inclined portion over which the end of the lead pipe is expanded, the outer portion of the coupling that sets outside the lead pipe having a reduced inclined portion adapted to clamp the Haring end of the lead pipe against the inclined :face of the interior coupling-section. It has also been heretofore proposed to provide the inclined portions of the coupling Where they bear upon the iiaring end of the lead pipe with annular ribs or teeth in order to more firmly bind the end of the pipe and guard it against slipping. This type of coupling, While effective to a certain extent, is found objectionable, because inasmuch as the outer section of the coupling,bein g threaded onto the inner section, moves in straight line the annular ribs or teeth cut upon the inclined face of the outer section also move in straight line, and consequently plow into or out into the lead. pipe, becoming embedded therein only in the direction of their straight line of motion. Hence it is that While such annular indentations serve in a measure to form a tighter joint between the daring end of the lead pipe and its coupling the annular ribs or teeth of the coupling do not as effectively serve to rigidly hold the flaring end of the lead pipe or guard it against Withdrawal or make as tight a joint as with my improved construction.

My invention consists in forming the interior face of the abruptly-inclined portion of the outer couplin g-section with a screw-thread of such pitch and shape that it Will become embedded and form a continuous thread upon the daring end of the lead pipe as the outer section of the coupling is screwed to place.

Referring to the accompanying drawings,

Figure l isa View in elevation, showing the manner of applying my invention. Fig. 2 is a detail View, in vertical section, through a portion ot' a vent-pipe and through a portion of a'lead pipe connected to niy improved coupling. Fig. 3 is a view in section through the outer coupling, showing the manner of forming the threads thereon.

A designates the Waste-pipe, andB the ventpipe, of a closet. D

C designates the section of lead pipe leading from the closet to the Waste-pipe, and C denotes the section of lead pipe leading to the vent-pipe B. The coupling whereby the section C of lead pipe is connected to the ventpipe B is the same in construction as the coupling whereby the lead pipe C is connected with the Waste-pipe A, and a description of one of these. couplings Will answer for both.

My improved coupling comprises an inner section D, provided, preferably, at one end with a threaded portion adapted to engage With the Waste or vent pipe, and adjacent this inner threaded portion the section D of the coupling will be furnished with a polygonal exterior d, whereby the coupling-section may be screwed to place. The outer portion of the coupling-section D will also be formed with a threaded part d', adapted to be engaged by corresponding interior threads e, formed upon the inner face of the enlarged portion of the outer coupling-section E. This enlarged portion of the outer coupling-section E will also be formed with a polygonal rim e', adapted to receive a Wrench for uniting the sections of the coupling together. The inner coupling-section D is formed with a reduced abruptlyinclined portion di, from Which preferably leads a straight portion di, adapted to enter the end of the lead pipe C for sonic distance. The outer coupling-section E is IOO also formed with a reduced abruptly-inclined portion e2, corresponding to the inclined portion d10 of the coupling-section D, and with a straight portion e3, corresponding With the straight portion d2 of the inner coupling-section. The inner face of the outer couplingsection E is formed with a continuous screwthread e4, which when the coupling-sections D and 'E are set together over the Haring inner end of thelead pipe C will form a corresponding screw-thread upon the outer face of the flaring end of the lead pipe, and thus firmly embed the threads e4 in such lead pipe. The screw-thread e4 is a considerably larger thread than the screw-thread that connects the two sections D and E together, and the crowns of the threads e4 are preferably rounded, so that as the sectionsare forced together the threads e4 will embed themselves into the flaring end of the lead pipe C without plowing into or cutting awajyT and so weakening the pipe. Inasinuch as there can be but comparatively slight movement of the outer couplingsection E after the thread e4 has come to bear upon the outer face of the flaring end of theand gas tight joint between the lead pipe andv the coupling, but will aid in preventing the accidental slipping of the coupling-section E upon the lead pipe notwithstanding any movel ment of this pipe incident to the shaking of the closet-bowl. It will be understood, of course, that the difference in the size of the thread e4 will vary according to the size of the couplings, but this thread should be so proportioned that as the coupling-sections are firmly joined together the thread e4 will be advanced such distance as to firmly embed itself into the outer face of the lead pipe. Preferably a shield II will be slipped over the coupling section D, adjacent .its annular shoulder d, in order to hide the joint between the coupling and the waste or vent pipe, although such shield is nopart of my invention.

Having thus described the invention, what I claim as new, and desire to secure by Letters Patent, is

A coupling for lead pipes comprisinga section D having formed integral therewith a cylindrical eXteriorly-screwthreaded portion d' and a reduced abruptly-inclined forwardlyextending plain portion d10, in combi-nation with the exterior coupling-section E having a cylindrical interiorly-threaded portion to engage the threadedportion dlv of the section D and having in piece therewith an abruptlyin'clined portion e2 corresponding with the abruptly-inclined portion d10 of the sectionD and provided upon its interior with a continuous screw-thread adapted to form a spiral'thread in a lead pipe interposed between the sections D and E, substantially as described.

PHILIP H. GUNDERMANN.

Witnesses:

Gno. P. FISHER, J r., ALBERTA ADAMICK. 

